THEY'RE young, fun and obsessed with super-bright lippy, but MKR's outgoing twins Helena and Vikki Moursellas, 25, have revealed a family tragedy which inspires their efforts in the competition.

The sisters are cooking their trademark "Greek with a modern twist'' in honour of their late father.

``He passed away when we were 12-years-old,'' Vikki said. "We've got heart disease in our family, so he suffered from a heart attack and passed away suddenly.

"Our mum has been absolutely amazing. She's been a very strong lady. She made sure that she took us on lots of holidays as kids. Made sure that we knew everything was going to be OK.''

Helena and Vicki on their competitors:

Annie and Jason, NSW, cheesemakers: (Vikki) We love Annie and Jason. Traditional, country bumpkins. They've got beautiful hearts. Chloe and Kelly, WA, well-travelled friends: (Helena) One word, fake. Paul and Blair, QLD, surfer dads: (Vikki) We got very, very close to them, the older brothers we've never had. Deb and Rick, SA, married 38 years: (Helena) They were our MKR parents. Andrew and Emilia, ACT, newly dating: (Vikki): We felt so bad for them. They are really nice. He might come across as awkward but they're great, humble people.

Although they were young when he died, Helena said the pair have good memories of their father, and like to think he would be impressed by their efforts in My Kitchen Rules.

"Dad would be very proud of us,'' she said. "He's always in our heads. Throughout the show it was something that kept us going. There were times when it was pretty hard. He has definitely pushed us through.''

Helena (the brunette one) and Vikki (the blonde one) have burst into MKR's fifth season brimming with confidence and catchphrases, such as "We got this'' and the less-catchy, "t-winning''.

News_Image_File: Tragic family secret revealed ... Helena and Vikki Moursellas at the launch of the 2014 season of Channel 7's My Kitchen Rules.

Vikki in particular has quickly become known for her not-so-savvy comments, suggesting they each have "half a brain''. Or, put differently,"We're one brain, and two people.''

"I've said some silly things, but that's all right, it's entertaining,'' Vikki said. "I never regret anything I said. Obviously ... I'm like, `oops' but I'm just being me, and I say funny, silly things.''

WILL WILL WIN MY KITCHEN RULES? TELL US BELOW

Helena and Vikki grew up in Adelaide, with no other siblings. Mum Sophie says they were outgoing from a young age.

"It was hard being a mother and father to my daughters since my husband passed away, but I was lucky because I had a lot of help from my mother and father bringing them up," she said. "Their father Nick loved food, cooking and entertaining and was very good at all three. Nick would be so proud of the girls."

News_Rich_Media: On MKR, close friends Chloe and Kelly expressed their distaste for the tart served by Andrew and Emelia. Courtesy: My Kitchen Rules, Seven Network

The sisters moved to Melbourne a couple of years ago, where Vikki studied graphic design and Helena attended Melbourne Radio School.

"We just felt like Adelaide was too small for us, not many opportunities (there) for us,'' Helena said.

"We want to try everything,'' Vikki said. "Travel the world, try different types of ... what's the word? Different types of jobs and stuff.''

The girls are well-travelled, although they don't drop it into every conversation like WA competitors Chloe and Kelly, who have described Helena and Vikki as "not the sharpest tools in the shed''. Helena reckons the two teams share a love-hate relationship.

"More on the hate side, as bad as that sounds,'' she said. "We just clashed all the time. We're actually very similar, we love to travel, we love food, and in conversations, we just tried outdoing each other.

"Throughout the competition it got more and more feisty, we wanted to beat them more than anyone else.''

MKR, hosted by celeb chefs Pete Evans and Manu Fieldel, has been a consistent ratings winner for Channel 7 since it premiered in 2010. Last year's final - which saw Dan and Steph declared the winners - was watched by over two million people.

News_Rich_Media: Sunday's episode of My Kitchen Rules is expected to be a fiery clash between the girls. Courtesy Channel Seven.

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